Bioluminescence

Subject : Science and technology

Concept : Biotechnology

A stretch of the beach at Bheemili near Visakhapatnam glows due to bioluminescence.

Bioluminescence

Bioluminescence occurs mainly due to the presence of single-celled organisms called dinoflagellates that produce light when disturbed.
Various other marine species such as sponges, jellyfish, worms, species of fish, arthropods, echinoderms and unicellular alga also exhibit bioluminescence.
Bioluminescence is a type of chemiluminescence, i.e. it involves a chemical reaction which produces light.
Such chemical reactions involve two unique chemicals namely luciferin and luciferase.
Luciferin is the compound that produces light and it acts as the substrate.
Luciferase is an enzyme or a catalyst that interacts with a substrate to affect the rate of a chemical reaction.
Photoprotein can also act as a catalyst in such reactions.
The phenomenon of bioluminescence on beaches is seen to be a natural phenomenon.
Bioluminescence is a “cold light”.
Cold light means less than 20% of the light generates thermal radiation or heat.
In the case of Visakhapatnam, bioluminescence is said to be a result of an algal bloom of the dinoflagellate species of noctiluca and ceratium.
Bioluminescence has been witnessed on some other beaches in India including Havelock Island in the Andamans, Thiruvanmiyur Beach in Chennai, Mattu Beach in Karnataka, Bangaram Island in Lakshadweep and Kerala’s Kumbalangi.

Implications

Bioluminescence may not be harmful to humans but it can have significant implications on the marine ecosystem as phytoplanktons are consumed by fish and the harmful algal blooms have led to mass mortality of fish species in the past.
Further, the rapid algal growth of noctiluca is attributed to environmental changes such as sudden low salinity or disturbance by pollutants.